The present invention relates to threaded plastic bottles, especially polyethylene terephthalate, and closures therefor especially useful for carbonated beverages. The bottle-closure combination requires simple construction and the assurance of proper sealing. This is especially important where carbonated beverages are involved. In addition, the re-sealing operation must be simple to perform and also assure proper sealing.
A resilient ring or gasket is frequently placed between the rim of the container and the engaging surface of the cap in order to effect a pressure tight seal. However, with frequent use the gasket often deteriorates or is inadvertently discarded. Other designs are subject to disadvantages. Complex rim configurations are often difficult to use or are subject to foreign material becoming embedded in the rim. Also, complex collar designs often become damaged as during stacking in shipment.
It is therefore a principal object of the present invention to provide a plastic closure for use with a deformable container which is simple in construction and easy and convenient to use.
It is a further object of the present invention to provide a plastic closure which effectively obtains sealing of internal bottle pressure or carbonation even after repeated use.
It is a still further object of the present invention to provide a plastic closure which is not based on complex design features.
Further objects and advantages of the present invention will appear hereinbelow.